Meter vane position sensing controller

ABSTRACT

A meter movement controller has a movable meter vane, in the form of a disk of electrically conductive metal, movable between transmitting and sensor plates of a condenser to vary the transfer of energy between the plates. An SCR is arranged to be connected, in series with a diode, across a low-voltage source of AC potential at commercial frequency, and its anode is connected to the transmitting plate through a further condenser. A voltage divider is connected across the source in series with the diode, and the junction of the voltage divider is connected to the gate of the SCR. When the positive half wave of AC potential reaches a preselected potential, such as 100 volts, a triggering pulse is applied to the gate of the SCR to trigger the SCR conductive. This applies a 100-volt pulse to the transmitting plate of the condenser. A transistor amplifier, including a second SCR, connects the sensor plate to a control means, such as a relay winding. The relay winding is thus energized as a function of the transfer of energy between the condenser plates as modulated as a function of the position of the meter vane.

United States Patent Beling [54] METER VANE POSITION SENSING CONTROLLER [72] Inventor: Thomas E. Beling, Framingham, Mass.

[73] Assignee: Sigma Instruments, Inc., South Braintree,

Mass.

[22] Filed: Oct. 22, 1970 [21] Appl. No.: 83,033

[451 Feb. 15,1972

Primary Examinerl.. T. Hix AttmeyMcGlew and Toren 7] I ABSTRACT A meter movement controller has a movable meter vane, in the form of a disk of electrically conductive metal, movable between transmitting and sensor plates of a condenser to vary the transfer of energy between the plates. An SCR is arranged to be connected, in series with a diode, across a low-voltage [52] US. Cl ..3l7/148.5 R, 317/1485 B, 3 l 7/D1G. 2, source of AC potential at commercial frequency, and its 340/266 anode is connected to the transmitting plate through a further [5 l Int. Cl ..II0lh 47/32, G081) 21/00 condenser. A voltage divider is connected across the source in Field Searchm "317/1435 1485 series with the diode, and the junction of the voltage divider is 340/266 connected to the gate of the SCR. When the positive half wave of AC potential reaches a preselected potential, such as 100 [56] Ree'ences Clted volts, a triggering pulse is applied to the gate of the SCR to trigger the SCR conductive. This applies a 100-vo1t pulse to UNITED STATES PATENTS the transmitting plate of the condenser. A transistor amplifier, 2,339,496 9 Moore, Jr ..3 7/l48-5 R including a second SCR, connects the sensor plate to a control ,179 7/1959 Knudsen ..3l7/ 148.5 R means, such as a relay winding. The relay winding is thus ener- QUICk R gized as a function of the transfer of energy between the con- 2,947,875 8/1960 Beck ..317/148.5 R denser plates as d l d as a f ti f the position of the L0cher..... 2 mete vane 3,032,692 5/1962 Mulligan.. ....317/D1G. 2 3,196,321 7/1965 Crowdes ..317/148.5 R 10 Claims, 1 Drawing Figure la I0 4, ll

2/ 5 AR" I 27 45 r l6 .I [F I t 1;

:0 L I R7 I8 20 R2: 1 I7 3! g/T T wave of the AC source attains a 1 METER VANE POSITION SENSING CONTROLLER BACKGROUND OF THE INVENTION Meter movement controllers, of the contactless variety, usually sense the meter position by one of three methods. One method involves optical sensing, in which the meter vane interrupts a light beam directed on a photosensitive device. A second method uses inductive volves capacitive coupling, wherein the transfer of highfrequency energy from an oscillator circuit is modulated or altered by a metallic meter vane.

While all three generally used arrangements are effective to perform the desired control, they require components and the SUMMARY OF THE INVENTION To provide the large nected across a low-voltage source of AC potential of comample, the voltage divider applies a pulse to the main SCR to trigger the latter conductive. In turn, this applies the lOO-volt commercial AC source for energization, and involves very simple solid state circuitry for energizing a control means in accordance with the position of a meter vane.

An object of the invention is movement controller.

Another object of the invention to provide an improved meter is to provide such a meter movement controller involving a capacitive coupling and supin the form of large amplitude, fastto provide such a meter inexpensive, and utilizes bodiment thereof as illustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING In the drawing, gram of a meter tion.

the single FIGURE is a schematic wiring diamovement controller embodying the inven- DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, the illustrated meter movement controller has terminals 11 and 12 arranged for connection across a low-voltage source of AC potential, such as a l-volt 12 in and the gate of SC R 20 is connected to junction point or tap 18 of voltage divider l5.

The anode of SCR 20 is connected, through a condenser 22,

to the transmitting plate or electrode 26 of a main condenser trodes 26 and 27 is the position of meter vane 30.

The energy transferred from electrode 26 to electrode 27, as modulated or changed by the position of vane 30, is used to of main condenser 25 and the gate of SCR 45. Amplifier 35 includes cascade connected NPN-transistors 36 and 37 with associated resistors Rl-R6 and a condenser Cl..A condenser C2 connects the emitter of transistor 37 to the gate of SCR 45, and a resistor R7 is connected between this gate and conductor l4. f

In response to a predetermined transfer of energy between condenser electrodes 26 and 27, as determined by the position of vane 30, the transistor amplifier supplies a signal to the gate of SCR 45 to trigger SCR 45 conductive thus, in effect, conbetween conductors l3 and 14 to relay winding 40 may be energized at a predetermined high meter reading, to effect such principles.

What is claimed is:

l. A meter movement controller, utilizing a meter having a movable vane, comprising, in combination, a movable vane of electrically conductive metal; a condenser having a transthe position of said vane.

2. A meter movement controller, as claimed in claim 1, in which said pulse generating means comprises an SCR arcluding a diode connected between one tenninal of the source and said SCR.

4. A meter movement controller, as claimed in claim 3. in

which said instantaneous potential responsive means comprises a voltage divider connected in series with said diode and in parallel with said SCR; and means connecting a tap of said voltage divider to the gate of said SCR.

5. A meter movement controller, as claimed in claim 4, including a capacitor connected between the anode of said SCR and said transmitting electrode.

6. A meter movement controller, as claimed in claim 5, including a second capacitor connected between said vane and electrical neutral.

7. A meter movement controller, as claimed in claim 4, in which said energy transfer detecting circuit comprises a transistor amplifier connected between said sensor electrode and said control means and controlling energi'zation of said control means.

8 A meter movement controller, as claimed in claim 7, including a second SCR connected. in series with said control means, across the source; and means applying the output of said amplifier to the gate of said second SC R.

9. A meter movement controller, as claimed in claim 8. in which said control means comprises a relay winding shunted by a capacitor.

10. A meter movement controller, as claimed in claim 9, in which said means applying the output of said amplifier to the gate of said second SCR comprises a capacitor connected between said amplifier and said gate. 

1. A meter movement controller, utilizing a meter having a movable vane, comprising, in combination, a movable vane of electrically conductive metal; a condenser having a transmitting electrode and a sensor electrode; said vane being movable between and parallel to said electrodes to vary the transfer of energy between said electrodes as a function of the position of said vane; pulse generating means connected to said transmitting electrode and operable to apply, to said transmitting electrode, a series of large amplitude pulses; control means; and an energy transfer detecting circuit connecting said control means to said sensor electrode and operable to effect energization of said control means as a function of the position of said vane.
 2. A meter movement controller, as claimed in claim 1, in which said pulse generating means comprises an SCR arranged to be connected across a source of AC potential having an electrical neutral and to said transmitting electrode; and means operable, responsive to instantaneous potentials of said source, to trigger said SCR conductive.
 3. A meter movement controller, as claimed in claim 2, including a diode connected between one terminal of the source and said SCR.
 4. A meter movement controller, as claimed in claim 3, in which said instantaneous potential responsive means comprises a voltage divider connected in series with said diode and in parallel with said SCR; and means connecting a tap of said voltage divider to the gate of said SCR.
 5. A meter movement controller, as claimed in claim 4, including a capacitor connected between the anode of said SCR and said transmitting electrode.
 6. A meter movement controller, as claimed in claim 5, including a second capacitor connected between said vane and electrical neutral.
 7. A meter movement controller, as claimed in claim 4, in which said energy transfer detecting circuit comprises a transistor amplifier connected between said sensor electrode and said control means and controlling energization of said control means.
 8. A meter movement controller, as claimed in claim 7, including a second SCR connected, in series with said control means, across the source; and means applying the output of said amplifier to the gate of said second SCR.
 9. A meter movement controller, as claimed in claim 8, in which said control means comprises a relay winding shunted by a capacitor.
 10. A meter movement controller, as claimed in claim 9, in which said means applying the output of said amplifier to the gate of said second SCR comprises a capacitor connected between said amplifier and said gate. 